Visiting Canada, want to block data

Canada is incredibly close, and I'm going to be visiting it again in a week but the first time since having a smartphone. I'd like to leave the phone on for voice calls and wifi (I've researched and understand the per-min rates), but I want to guarantee that not 1 byte of data will transfer and incur me some obscene surcharge.

I would suspect that turning off data roaming would suffice. I would also call AT&T and ask them what to do so it's on record just in case. Then if something happens you can say "well this is what YOU told me do!".

It worked PERFECT for me and will allow you to turn on/turn off mobile data with the press of a small widget. This also works without having to reboot your phone for the data status change to take place! (APNdroid/QuickSettings requires a phone reboot for data to be turned on/off)

ATT will actually text you when you leave your data area and start roaming... something like "Data $15/MB while roaming"
We went to Sarnia Canada recently and while near the border, no problems, but further in we received that msg.

I travel to Canada regularly - turn off data roaming is all you need. Text messages use the voice network, so will still get those.

AT&T offers some Canada plans - they are expensive but cheaper then going without them. I usually get the 20MB of data for $29 (i think) and it lets me Exchange sync for about 3 days. There is also a $5 voice plan, that reduces the cost of per minute voice calls.

If you are brand new to AT&T they need to provision your phone for international travel, or you will get there and not be able to make or receive calls. If this is your first trip abroad, call them and make sure everything is set.